In poultry hatcheries and other egg processing facilities, eggs are handled and processed in large numbers. The term “processing” includes treating live eggs with medications, nutrients, hormones and/or other beneficial substances while the embryos are still in the egg (i.e., in ovo). In ovo injections of various substances into avian eggs have been employed to decrease post-hatch morbidity and mortality rates, increase the potential growth rates or eventual size of the resulting bird, and even to influence the gender determination of the embryo. Injection of vaccines into live eggs have been effectively employed to immunize birds in ovo.
There are a number of applications for which it is desirable to inject eggs containing early avian embryos. For example, it may be desirable to deliver a substance to an early embryo, such as a blastoderm. To illustrate, it may be desirable in the poultry industry to manipulate an early embryo in ovo to introduce a foreign nucleic acid molecule (i.e., to create a transgenic bird) or to introduce a foreign cell(s) (i.e., to create a chimeric bird) into the developing embryo. Unfortunately, blastoderm visibility is very poor in the presence of the inner shell membrane of an avian egg. Moreover, blastoderm position may not be in the most favorable location for receiving a substance.
In addition, there a number of applications for which it is desirable to remove samples from eggs, including from early avian embryos. Further, there are a number of applications for which it is desirable to insert a sensing device inside an egg containing an embryo to collect information therefrom.
Current methods of inserting devices into avian eggs containing early embryos may be undesirable because they may result in unacceptably low hatch rates, and may cause other problems, such as the introduction of air bubbles into an egg, damage to extra-embryonic membranes or to the embryo itself, or a combination of these factors. Accordingly, there is a need in the art for improved methods of inserting devices into avian eggs.